D&D My character is not interested in flirty NPX

I’m playing a Drunken Master Wood Elf Monk named Jade. Last session, my party after about a weeks worth of traveling had finally made it to their destination. Our party rested up and then decided to stock up on supplies before meeting our contact. My character (who is a sage and is and loves books) decides to go to the local bookshop and purchase some books along with some parchment. As Jade was leaving, the NPC who was running the bookshop scribbles a note on one of her pieces of paper. She doesn’t read it until late into night. After reading it she finds out that the bookshop NPC (I don’t remember his name) wanted to meet her at one of taverns in town. Jade meets up with him and he starts flirting with her.

My character Jade is extremely awkward in social situations and is completely obvious to people hitting on her. She blushes and then luckily the contact (a monk whom her party was planning to meet with) takes her aside to speak with her.

The NPC is clearly super into my character but my character isn’t. How should I go about role playing this out and being able to kindly reject him?